Better support for openai-like providers and dynamic models in AI SDK

[Sytten]

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Description

Right now we support an url in the openai provider, but it is a hack since you have to then call it like: openai/<MODEL CLEARLY NOT FROM OPENAI> and the plugins can't know those models. I think we need to be able to add new providers and then call them like <provider-alias>/<optional sub model>/<model>. We also likely need an API to retrieve a list of available models so the plugins can know what to display.

Use cases

• Better support of local models and proxies like litellm